US and World Avalanche Accident Statistics

The Colorado Avalanche Information Center (CAIC) has a detailed database of the US and World Avalanche Accident Statistics. Their statistics and graphs are very comprehensive and separate accidents by year, state, and user groups. They also provide written accident reports which can be quite interesting and informative.

Local Avalanche Accident Reports

Posted below are accident reports from our advisory area for the current season.

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BEEHIVE BASIN AVALANCHE FATALITY

20 JANUARY 2008

SYNOPSIS:

Two skiers were touring in Beehive Basin, located north of Big Sky, MT in the northern Madison Range, when they triggered an avalanche. One was caught, buried and died of head trauma at the scene. The avalanche released on a southwest facing, wind-loaded slope. The slope angle was approximately 40+ degrees with the crown face 1 ½ to 3 feet deep. The avalanche was estimated to be 600 feet wide, 500 feet vertical and to have a runout angle of 25 degrees. US Classification of the avalanche is SS-AS-D3-R4-O.

GPS Coordinates for the slope is

N 45.3224

W 111.3828

Elevation of crown is approximately 9,000 feet.

MAPS AND PHOTOS:

Maps of the accident site with red crosshairs denoting slope of avalanche:

(1:50,000)

http://www.topozone.com/map.asp?lat=45.3224&lon=-111.3828&datum=nad83&u=5&layer=DRG&size=l&s=50

(1:200,000)

http://www.topozone.com/map.asp?lat=45.3224&lon=-111.3828&datum=nad83&u=5&layer=DRG&size=l&s=200

Aerial photo of the path-marked: http://mtavalanche.com/data/images/1201459028.jpg

Aerial photo of the path: http://mtavalanche.com/data/images/1201002418.jpg

Photo of the crown: http://mtavalanche.com/data/images/1201458716.jpg

Photo from toe: http://mtavalanche.com/data/images/1201458891.jpg

WEATHER:

The weather data for this incident is from the Yellowstone Club and Big Sky Ski areas approximately 5 miles southwest of the avalanche.

Sunday, January 20th was a cold, cloudy day with daytime temperatures of -6F at 9,000 feet. Since Tuesday, January 15th, the mountains got snow every day which totaled 35 inches the morning of the accident. Winds were westerly the 15th through the 19th at 15-30 mph. The early morning of the 20th they blew from the northeast at 10 mph.

AVALANCHE:

The victim, TS (20), and LK skied into Beehive Basin for a tour. Beehive Basin is a very popular backcountry area because of its varied terrain and close proximity to a trailhead. They knew the avalanche danger was rated CONSIDERABLE and had no agenda about skiing particular slopes. They wanted to tour around and dig a few snowpits. They were avid backcountry skiers, had taken a Level 1 avalanche class and carried the appropriate rescue gear. They were concerned about the avalanche danger and talked about it openly among themselves and others.

They accessed the ridge between Beehive and Bear Basins via subdivision roads. They dug 2 snowpits, one of which was near the ridgetop on the Beehive side. They found faceted snow near the ground, but their stability tests were unimpressive and LK mentioned to me that maybe the pits weren’t dug in great spots.

From the top of the Beehive/Bear ridge they could see an open slope below them and a rib leading into Beehive Basin. This rib borders the slope to the west and is where most people skin uphill in order to access the ridge. While on the ridge TS and LK watched 4 skiers punch the “skiers-right side” of the hill—all at once. TS and LK then moved down the ridge, pulled off their skis and met J and his girlfriend D.

TS and LK were “genuinely concerned about the snow stability” according to both D and J. They wanted to descend the slope into Beehive Basin. They asked J and D about it (stability) and after a brief conversation J told them to head down the ridge but not go too far left where there’s a gulley.

LK and TS headed downhill and found themselves slightly left of where they wanted to be. They were on a shallow angled slope with a small rib 10 feet to their right they wanted to reach. TS skied out first when he triggered only 4 feet away from LK. The snow where LK was standing cracked and moved a few inches, but not avalanche. TS disappeared down the slope.

A few minutes later J was 3 turns down the rib when he saw the 2 foot crown. He yelled up to D to put her transceiver on “receive” and then proceeded down the slope searching. He saw LK booting uphill since he missed TS on his first pass. They found TS with a part of his pack exposed. He was face down, head first in a V notch of a tree. Pulseless and obviously dead from massive trauma a call was placed to 911.

SEARCH AND RESCUE:

The avalanche happened at approximately 1530. J reached TS within 2 minutes of starting his search, and he and LK extricated TS within 10 minutes. His pack was barely visible at the surface. After the initial 911 call Big Sky Search and Rescue (BSSR) was dispatched. Over the next 4 hours BSSR got a team of skiers and snowmobilers to the site, packaged up the victim and brought him to the trailhead.

SNOWPACK:

Scott Schmidt, avalanche forecaster at the GNFAC, went to the avalanche the next day to conduct an investigation. He found the snowpack at the crown to be thin, faceted and unstable. The avalanche was 18” to 36” deep, 600 feet wide, 500 feet vertical and ran a slope distance of 1,500 feet. At the crown the slope was 40+ degrees steep. The slope faced 220 degrees (SW) and was loaded from westerly winds cross-loading the slope as well as recent northeast winds the day of the slide. J and D noted active wind-loading during the day of the avalanche.

At the crown line Scott found the snow to easily fracture on a 3 cm thick layer of 5mm facets. He dug another pit on the ridge where the group of skiers descended and found the snow to be 3 feet deeper and much stronger. D noted that all the new snow from the last 5 days made the slope below look uniform in depth, when in fact it wasn’t.

The avalanche danger in the northern Madison Range this day was rated CONSIDERABLE on all wind-loaded slopes as well as any slope steeper than 35 degrees.

Snowpit profile in Crown: http://mtavalanche.com/data/images/1201461711.jpg

Snowpit in Flank: http://mtavalanche.com/data/images/1201461589.jpg

Please contact me for more information or if you have any questions. I can be reached at 406-587-6984 or dchabot@fs.fed.us

Doug Chabot

Director

Gallatin National Forest Avalanche Center

www.mtavalanche.com

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WINDY PASS AVALANCHE BURIAL

Check out our photos and video clip of this accident at:

http://www.mtavalanche.com/photos/photos.php

http://www.mtavalanche.com/videos/

12 January 2008

SYNOPSIS:

One snowmobiler was caught, buried, and recovered uninjured in an avalanche that occurred near Windy Pass in the Portal Creek drainage of The Gallatin Range in southwest Montana. The avalanche released on a wind-loaded slope, with a northerly aspect. The slope angle was in the high 30’s at the crown. The crown was 4 feet at its deepest point, and 150 feet in width. The avalanche ran i - approximately 800 vertical feet, with a wasangle of 24 degrees. The avalanche triggered by the victim as he descended the chute after making 5 or 6 passes on the slope. The distance from the trigger point to the avalanche crown was approximately 200 feet slope distance. US classification of the avalanche is HS-AM-R3-D2-O.

WEATHER:

Eight to twelve inches of new snow fall in the two days prior to the avalanche. Strong southerly winds had loaded this path several days before the avalanche. Wind in the 48 hours prior to the slide had been northerly. Temperatures were seasonal with highs in the mid to upper teens.

AVALANCHE:

20 year old Travis Poor and his partner were highmarking to the right of Windy Pass. Travis had made 5 or 6 passes on the slope before it released. On his last attempt he climbed to within 30 feet of the ridgeline. The avalanche released as he descended the chute and over-ran him near the bottom of the slope. The avalanching snow hit Travis from behind and launched him and his sled toward a stand of trees. Seeing the danger of being strained through the trees Travis jumped from his sled, was tumbled several time, and came to rest buried under 2 – 3 feet of snow. His sled was carried thought the trees and came out the other side in several pieces

RESCUE:

Travis’ partner was climbing the next chute over. When he came down from his pass he saw the avalanche debris and started over to the scene. Three passing snowmobilers from another party arrived simultaneously and the group started a beacon search. When they got close to the burial site they say the toe of Travis’ boot sticking out of the snow and they were able to extricate the unconscious victim within ten minutes from the time they started searching. He was breathing when they dug him out of the snow and he regained full consciousness within 10 minutes. The group built a fire, warmed the victim and he was able to ride out on the back of his buddies sled.

SNOWPACK:

The snowpack on this slope consisted of a hard ice crust near the ground. Eighteen centimeters of weak faceted snow was sitting on the crust, and these weak crystals where supporting 2 – 4 feet of wind deposited snow. Total snow depth at the likely trigger point was 130 centimeters.

If you have questions about this incident please feel free to call me at 406-587-6984 or email me at sschmidt@fs.fed.us.

Scott Schmidt

Avalanche Specialist

Gallatin National Forest Avalanche Center

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Notes Regarding Avalanche Incident near Lulu Pass on 2 January 2008

Date: 2008-01-02

Submitted By: GNFAC

Place: Scotch Bonnet Mountain near Cooke City, Montana

State: MT

Country: USA

Fatalities: 0

Activity: SNOWMOBILE

Summary: One snowmobiler was caught and buried 4-5 feet deep. His four partners rescued him within about 15 minutes. He was not injured. They all carried avalanche rescue beacons, probe poles and shovels.

This brief description is based on a phone conversation with a Forest Service employee who responded to the incident as a member of the Cooke City Search and Rescue Group.

At approximately 4:15 p.m. on 2 January 2008, a party of five snowmobilers from North Dakota was high marking on Scotch Bonnet Mountain near Cooke City, Montana. One rider got stuck about half way up a steep slope. His four partners were riding on the slope when it fractured. The stuck rider was at the crown face and was not caught in the slide. Three riders managed to ride off of the slope and were not caught. One rider was caught and buried 4-5 feet deep.

His partners used avalanche rescue beacons, probe poles and shovels to locate and uncover the buried rider. The rescue took approximately 15 minutes. The patient was cyanotic and wasn’t breathing. He started breathing shortly after his partners shook him. He wasn’t injured. He was a lucky lad.